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Fluidetom_12222's avatar
Fluidetom_12222
Icon for Cirrus rankCirrus
Oct 04, 2013

How to use only part of the uri ?

Hey, I have a very simple iRule to redirect the traffic to another URL if the uri start with a string (in my case "/api"). when HTTP_REQUEST { if { [HTTP::uri] starts_with "/api" } { ...
application delivery
design
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Kevin_Stewart's avatar
Kevin_Stewart
Icon for Employee rankEmployee
Oct 04, 2013

Jurgen abd Samir have good examples. Here's what these might look like:

when HTTP_REQUEST {
    if { [string tolower [HTTP::uri]] starts_with "/api" } {
        set newuri [string range [HTTP::uri] 4 end]
        HTTP::redirect "https://service.test.com:7002/Test$newuri"
    }
}

or 

when HTTP_REQUEST {
    if { [string tolower [HTTP::uri]] starts_with "/api" } {
        set newuri [string map -nocase {"/api" ""} [HTTP::uri]]
        HTTP::redirect "https://service.test.com:7002/Test$newuri"
    }
}

The most significant difference between these two examples is timing:

% set uri "/api/foo/bar"    
/api/foo/bar
% puts [string range $uri 4 end]
/foo/bar
% puts [string map {"/api" ""} $uri]
/foo/bar
% time { set newuri [string range $uri 4 end] } 100000
0.72165 microseconds per iteration
% time { set newuri [string map {"/api" ""} $uri] } 100000
0.80794 microseconds per iteration

The string range command is only slightly faster.